This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Cytosine methylation (http://www.ks.uiuc.edu/Research/methylation/) is a chemical modification on DNA, which involves replacing a hydrogen atom by a methyl group at the 5' position in cytosine. Methylation of DNA is one of the most important mechanisms in epigenetics. Without changing the sequence of DNA, methylation can alter the expression levels of genes [1]. The physical mechanism underlying methylation is presently under intense study, yet current measurement methods for methylation profiles are still lacking. Previous experiments suggest that methylation can affect DNA properties by changing its structure or its dynamics [2, 3].